Discussions

I am trying to dehumidify a residence: know that some say yes to first level dehumidification: some people say no, you have to do the basement or crawl space first.  
 
I can see the comfort point of view to dehumidifying a basement, but the first level, I am not so sure. I see problems with dehumidifying one space and not another in that you create a moisture gradient: the moisture could just move from high to low, across an unsealed wall or basement. It doesn't make sense to dehumidify the first level, if the humidity is travelling from the basement.  
 
Would measuring the moisture levels at various levels (basement, first, and/or second) be a good strategy? Could you then plan a moisture management strategy based on say relative humidity.  
 
Is there a science to this: could someone explain if our use of single level dehumidifiers is a bunk idea.  
 
I would also tend to think that the furnace system in combination with vapor barrier and insulation should be enough. If you have a humidity issue, is it not due to a lack of sealing between outside and inside of the house. (or excessive showering...)  
 
Edited by PiEyedSquire, 2019-08-28 21:39:43

Why not just get an air exchange system? That takes care of the whole problem... no more need for dehumidifiers as there are humidity controls on each level.  
It’s worked for me!

Your humidity in the basement will be higher than upstairs. If you dehumidify the basement it will also lower upstairs especially if you have a furnace moving air in the whole house. As for air exchangers they are not very efficient at removing humidity. Good for your shower or by your stove when boiling water but that’s about it. Also if humidity is high outside an exchanger will not lower humidity in the whole house. Also exchangers if run a lot increase your heating costs. A dehumidifier in the basement is the way to go.

Both ideas you have presented make sense: I will think about them in the days to come.

An air exchanger will only raise humidity in the summer months when its humid outside. In the winter an exchanger will bring in dry air and lower the humidity inside. But, like another poster stated, you will likely increase your heating bill.  
 
A dehumidifier in the basement, where the heavier and more humid air is, makes the most sense. Keep it in an area where air from the rest of the house can circulate to. Keep the furnace fan running for circulation. Ideally you would run a drain hose to a floor drain from the dehumidifier rather than emptying the bucket all the time.